Pressure pump



S. WfLTSE PRESSURE PUMP March 8, 1949.

3 Sheets-Sheet 1 Filed Aug. 6, 1945 INVENVTOR. Sumner Will's! March 8, 1949. s. WILTSE 2,464,014

. PRESSURE Pun? Filed Aug. 6, 1945 3 Sheets-Sheet 2 2 I i a a L Q I H n w V It I h I Ls" INVENTOR.

MA M4 Sumner M? Sc? Patented Mar. 8, 1949 UNITED STATES PATENT OFFICE PRESSURE PUMP Sumner Wiltse, Detroit, Mich.

Application August 6, 1945, Serial No. 609,227

6 Claims. 103-5) This invention relates to an improved method and apparatus for displacing or pumping fluids.

One of the principal objects of this invention is to displace fluid from a source of. supply to a point of distribution in such a manner that the delivery pressure of the fluid is substantially uniform regardless of the volume of the fluid displaced and the pressure at which the fluid is discharged from the pump outlet. More particularly, the invention has as one of its objects to deliver fluid at the desired pressure and volume with the minimum amount of pulsation at the pump outlet. Thus, severe impacts on associated equipment and destructive vibration of this equipment resulting from excessive pulsations of the operating fluid is prevented.

Another object of this invention is to flow fluid from the intake side of the pump to the delivery side of the latter through a helical passage which tends to dampen the pulsating action of the fluid before the latter is discharged from the pump.

Still another object of this invention is to provide a pump having a rotor formed with a helical projection co-acting with the pump casing to form a helical passage extending from the pump inlet to the outlet and responsive to rotation of the rotor to displace fluid to the outlet opening under a pressure which varies in accordance with the diameter of the rotor, speed of rotation of the rotor. length of the helical passage and the helix angle of the projection. A fourth object of this invention is to provide a pump of the above general type wherein the depth of the helical passage gradually decreases toward the outlet opening so as to provide an increased pressure on the fluid as it approaches the delivery side of the pump.

A still further feature of this invention is to provide a rotor having a helical projection of the character previously set forth which successively opens and closes the pump inlet opening at'predetermined intervals.

In addition to the foregoing, the present invention contemplates supplying fluid to the pump inlet opening by a rotary vane type auxiliary pump operated by the rotor and having the delivery or pressure side communicating with the main pump inlet.

The foregoing as well as other objects will be made more apparent as this description proceeds, especially when considered in connection with the accompanying drawings wherein:

Fig. 1 is a side elevation partly in section of a pump constructed in accordance with this invention;

Fig. 2 is an end elevation of the pump shown in Fig. 1;

Fig. 3 is an enlarged fragmentary sectional view of part of the pump shown'in Fig. 1;

Fig. 4 is a cross sectional view taken substantially on the plane indicated'by the lines 4-4 of Fig. 3;

Fig. 5 is a side elevation partly in section of a modified pump construction;

Fig. 6 is an end elevation of the pump shown in Fig. 5;

Fig. 7 is a cross sectional view taken substantially on the plane indicated by the lines l-l of Fig. 5;

Fig. 8 is a side elevation partly in section of still another embodiment of this invention; and

Fig. 9 is an end elevation of the pump shown n Fi 8.

Referring first to the embodiment of the invention shown in Figs. 1 to 4 inclusive, it will be noted that the reference character I 0 indicates a pump assembly comprising a casing l l and a rotor [2. The casing H is formed with a bore l3 closed at one end by the end wall H of the casing and closed at the opposite end by a plate l5 which is detachably secured to the adjacent end wall of the casing by fastener elements I6. The casing is formed with a laterally extending enlargement [1 adjacent the plate I5 and this enlargement is provided with an inlet passage [8. The outer end of the passage l8 communicates with a conduit I9 which in turn communicates with a suitable source of fluid supply and the inner end of the passage l8 communicates with the bore l3 through an inlet opening 20. As shown in Fig. 4 of the drawings the inlet opening 20 intersects the wall of the bore throughout an arc which extends for approximately around the circumference of the bore. The rear wall M of the casing H is formed with an outlet openin'g2l and the latter communicates with a discharge or delivery conduit 22.

The rotor I2 is in the form of a shaft and is journaled in the bore [3 for rotation relative to the casing l I. The end of the rotor adjacent the plate i5 is formed with an enlargement 23 and the latter occupies a position in a recess 24 formed in the adjacent end of the casing by counterboring the bore 13. The opposite sides of the enlargement 23 respectively engage the inner surface of the plate i5 and the annular" shoulder 25 formed by the counterbore or recess 24. Thus, the enlargement 23 acts as a thrust bearing to resist axial movement of the rotor l2 relative to the casing I l. The plate i5 is provided with a central opening 26 through which to a suitable electric motor diagrammatically indicated in Fig. 1 of the drawings by the reference character 21.

Fluid medium entering the bore l3 from the supply conduit I9 is displaced axially of the bore from the inlet opening 20 to the outlet opening 2| in response to rotation of the rotor l2. For accomplishing this result the rotor is formed with a helical groove 28 which extends from the inlet opening 20 to a point adjacent the delivery end of the rotor. The groove is formed in the periphery of the rotor in such a manner that the resulting helical projection 29 simulates a square thread in appearance having a relatively small helix angle and having a width at the periphery sufllcient to afiord ample bearing area for the rotor. 1

As shown particularly in Figs. 3 and 4 of the drawings the rotor is provided with an arcuate portion 30 at the receiving end of the helical groove in a position to register with or overlap the inlet opening 20. This arcuate portion extends for approximately 225 of rotation of the rotor and the remaining portion of the rotor is recessed as at 3|. The recess 3| extends throughout approximately 135' of rotation of the rotor and, since the inlet opening 20 extends throughout 90 of rotation of the rotor, it follows that the inlet opening remains in communication with the recess 3| throughout substantially 225 of rotation of the rotor. The recess 3| communicates with the receiving end of the helical groove 28 and the fluid admitted to 'the recess from the inlet openin 20 is directed into the helical groove by the tapered wall 30' on the portion 30. Actually the wall so is fashioned to impart an impetus to the incoming fluid in the direction of rotation of the rotor, and thereby assists in charging the helical groove 28 with the fluid. Also theflow of fluid from the inlet opening 20-into the recess 3| is assisted, because during the interval the inlet opening 20 is closed by the arcuate part 30 of the rotor, fluid is exhausted I therefrom and the resulting space is made available for the incoming fluid when the inlet opening is again opened.

It will, of course, be understood that'the rotor is rotated in the direction of the helix so that the fluid admitted to the groove 28 is displaced under pressure axially of the bore I3 toward the outlet opening 2| in the casin II. The fluid displaced to the delivery end of the helical groove 28 is directed radially inwardly of the rotor through a plurality of passages 32. The passages 32 extend from the base of the delivery end portion of the groove 28 to a bore 33 formed in the adjacent end of the rotor and the bore 33 in turn communicates with the outlet opening 2|. If desired, the depth of the groove 28 adjacent the delivery end of the latter may be gradually decreased toward the outlet opening 2| in order to substantially increase the pressure acting on the fluid during the final stages of the pumping operation.

It follows from the foregoing that the inlet port 20 is periodically opened and closed in response to rotation of the rotor l2. During the period that the inlet 20 is open fluid is admitted to the receiving end of the helical groove 28 and is displaced by the latter to the outlet opening 2|. The volume as well as the pressure of the fluid supplied to the delivery conduit 22 will, or course, depend upon the diameter of the rotor.

eed oi rotation of the rotor, length of the helical groove and tire helix angle. All or any oneof these factors may be varied to attain the operation required for the particular application of the pump. While it is true that the periodic opening and closing of the inlet 20 results ina pulsating action of the fluid at the receiving end oi the helical roove, nevertheless it will be noted that such'pulsations and the resulting vibrations are dampened to a substantial extent by conflning the flow of the fluid medium in a helical path. As a result fluid is delivered to the conduit 22 at a substantially uniform pressure and this is highly desirable in that it reduces harmful vibration in the associated equipment to a mini mum.

The embodiment of the invention shown in Figs. 5 to 7 inclusive is similar to the one previously described except that fluid is admitted to the inlet opening 20 by a relatively low pressure auxiliary pump. Owing to the similarity of the two constructions, corresponding parts thereof are indicated by the same reference characters. In detail, it will be noted that the end of the bore I3 adjacent the plate I5 is formed with an enlargement 35 which is eccentrically arranged with respect to'the axis of the bore l3 and forms an auxiliary pump chamber. One side of the recess 35 communicates with the inlet opening 20 by means of connecting passages 38 and 36a and the diametrically opposite side of the recess 35 communicates with an intake port 31. The intake port 31 in turn communicates with a source of fluid supply through a conduit 38 which is secured inv any suitable manner to the pump casing.

The rotor l3 has an enlargement 33 which is concentric with the axis of rotationof the rotor and is positioned in the recess or chamber 35. This enlargement not only serves the same purpose as the enlargement 23 previously described, but also acts as a rotor for the auxiliary pump. As shown particularly in Fig. 7, the enlargement 39 is formed with radial slots extending at right angles to each other and adapted to slidably receive suitable vanes 40. The radially outer ends I of the vanes 40 co-act with the adjacent cylindrical surface 4| of the chamber 35 upon rotation of the rotor l2 to force fluid underpressure from the intake port 31 to the inlet opening 20. Attention is called to the fact at this point that an accumulating chamber 20' is arranged in constant communication with the inlet opening 20 and passage 36a. Thus when the inlet opening 20 is closed by the arcuate portion 30 on the rotor, fluid delivered by the pump 33 is collected in the accumulator chamber 20' and is stored in the latter until the inlet opening is again opened. With the above arrangement,'fluid under pressure is supplied to the recess 3| and helical groove 28 during the interval the recess registers with the inlet opening an, and this is desirable in cases where higher pressures are required at the delivery side of the pump Ill.

The embodiment of the invention shown in Figs. 8 and 91s similar to the construction shown in Fig. 1 except that the conduit 22 is connected to the source of supply of the fluid to be pumped and the conduit l9 serves as a delivery conduit. Also in this construction the rotor I2 is rotated in a direction opposite the direction of rotation indicated in Fig. 1 of the drawings so that fluid may be displaced. from the opening 2| to the opening 20. In this connection it will be noted that the fluid admitted to the bore 33 in the rotor is subjected to the action of centrifugal force and Y to the action of suction created by rotation of the periphery thereof coacting with the inner surface of the bore to form a helical passage communicatin at one end with the outlet opening, a cylindrical part on the rotor having a bearing engagement with the inner surface of the bore at the receiving end of the helical passage for closing the latter and having an arcuate recess registerable with the inlet opening, said arcuate recess communicating with the entrant end of the helical passage and having provision for directing fluid from the inlet openin into said helical passage.

2. A pump assembly comprising a casing having an elongated bore provided with axially spaced inlet and outlet openings, a rotor journalled in the bore, a helical groove in the periphery of the rotor extending between the inlet and outlet openings, said groove cooperating with the inner surface of the bore to provide a helical passage having the delivery end communicating with the outlet openin and gradually decreasing in cross sectional area toward the outlet opening, a cylindrical part on the rotor having a bearing engagement with the outer surface of the bore at the receiving end of the helical passage for closing the latter and having an arcuate recess registerable with the inlet opening, said arcuate recess communicating with the entrant end of the helical passage and havin provision for directing fluid from the inlet opening into the helical passage, and means for rotating the rotor in the direction of the helix to displace fluid from the recess to the outlet opening.

3. A pump assembly comprising a casing having an elongated bore provided with axially spaced inlet and outlet openings, a rotor journalled in the bore and having an axially extending passage communicating with the outlet opening, a helical groove in the periphery of the rotor extending from the inlet opening in a direction toward the outlet opening and having radially extending ports in the delivery end portion connecting the groove to said passage, means for introducing fluid into the receiving end of the helical groove including a cylindrical part on the rotor having a bearing engagement with the bore at the receiving end of the helical groove for closing the latter and having an arcuate recess registerable with the inlet opening, said arcuate recess communicating with the entrant end of the helical groove and having provision for'directing fluid entering the recess into the helical groove.

4. A pump assembly comprising a casing having an elongated bore provided with axially spaced inlet and outlet openings, a rotor iournalled in the bore, a helical groove in the periphery of the rotor extending between the inlet and outlet openings, said groove cooperating with the inner surface of the bore to provide a helical passage having the delivery end communicating with the ill 6 outlet opening and gradually decreasing in cross sectional area toward said outlet opening, ports extending radially inwardly from the base portions of the groove adjacent the delivery end of the latter and connected to the outlet opening, a cylindrical part on the rotor having a bearing engagement with the inner surface of the bore at the receiving end of the helical passage for closing the latter and having an arcuate recess registerable with the inlet opening, said arcuate recess communicating with the entrant end of the helical passage and having provision for directing fluid from the inlet opening into the helical passage, and means for rotating the rotor in the direction of the helical groove to displace fluid from the recess to said outlet opening.

5. A pump assembly comprising a casing having an elongated bore provided with axially spaced inlet and outlet openings, means for displacing fluid under pressure from the inlet opening to said outlet opening including a rotor journalled in the bore and having a helical groove in the periphery thereof coacting with the inner surface of the passage communicating at one end with the outlet opening, a cylindrical part on the rotor having a bearing engagement with the inner surface of the. bore at the receiving end of the helical passage for closing the latter and having an arcuate recess registerable with the inlet opening, said arcuate recess communicating with the entrant end of the helical passage and having provision for directing fluid from the inlet opening into said helical passage, and an auxiliary pump driven by the rotor having inlet and outlet ports respectively connected to a source of fluid supply and to the inlet opening.

6. A pump assembly comprising a casing having an elongated bore provided with spaced inlet and outlet openings, an accumulating chamber communicating' with the inlet opening, means for displacing fluid under pressure from the inlet opening to the outlet opening including a rotor journalled in the bore and having a helical groove in theperiphery thereof coacting with the inner surface of the bore to form a helical passage communicating at one end with the outlet opening, a cylindrical part on the rotor having a bearing engagement with the inner surface of the bore at the receiving end of the helical passage for closing the latter and having an arcuate recess periodically registerable with the inlet opening, said arcuate recess communicating with the entrant end of the helical passage and having provision for directing fluid from the inlet opening into the helical passage, means for rotating the rotor in the direction of the helical passage, and an auxiliary pump driven by the rotor having intake and outlet ports respectively communicating with a source of fluid supply and with the accumulating 'chamb'er.

SUMNER WILTSE. REFERENCES orrEn The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,492,846 Holweck May 6, 1924 1,810,083 Norinder June 16, 1931 FOREIGN PATENTS Number Country I Date 152,767 Great Britain Oct. 21, 1920 167,350 Great Britain Aug. 11, 1921 173,043 Great Britain Dec. 16, 1921 

